Light trucks and similar vehicles with open cargo boxes share the problem of protecting the cargo box and its contents from snow, rain, or dirt which may cause damage to items being carried or stored in the cargo box. These vehicles also share the problem of securing these items from theft since the cargo box is open to passersby thereby leaving the contents vulnerable to theft.
Attempts to remedy these problems have been made by employing truck box caps which are fixed to the truck and enclose the truck cargo box. The majority of these truck box caps are of fixed dimensions having side walls the height of the truck cab, a fully enclosed top, and a relatively small door at the rear of the cap. Although these caps protect the contents of the cargo box from weather and theft the side walls and fully enclosed top can cause the further problem of making it impossible for the cargo box to be used with items which exceed the height of the sides without removing the cap from the truck.
Alonzo, Jr. et al. in U.S. Pat. No. 4,397,497 Aug. 9, 1983 suggests an Expandable Camper Body for a truck cargo box which has longitudinally telescoping side walls the height of the truck cab, a fully enclosed top, and a relatively small door at the rear of the cap. The telescoping side walls allow the operator to move a rear portion of the cap forward thereby leaving a rear portion of the cargo box open to hold large items. This cap is complex, does not have an aesthetically pleasing side profile when in the forward position, and allows for only a minority of the cargo box to be utilized when transporting large objects.
Drown et al in U.S. Pat. No. 4,944,550 Jul. 31, 1990 suggests a Telescoping Type Cover for Truck Beds and The Like which has longitudinally telescoping side walls the height of the truck cab, and a fully enclosed top. Like Alonzo the telescoping side walls allow the operator to move a rear portion of the cap forward thereby leaving a rear portion of the cargo box open to hold large items. This cap is also complex requiring a powered actuating system to move the rear portion of the cap forward, and does not have an aesthetically pleasing side profile when in the forward position.
Baranski in U.S. Pat. No. 4,974,898, Dec. 4, 1990 suggests a Telescoping Cover for Storage Facilities which can be used with a truck cargo box which has longitudinally telescoping cover members each having low side walls which are slightly higher than the cargo box walls, and a fully enclosed top. The telescoping cover members allow the operator to move a rear portion of the cover forward thereby leaving a rear portion of the cargo box open to hold large items. This cover does not allow for the storage of items which are much higher than the cargo box side walls when the cover is closed and does not have an aesthetically pleasing side profile when in the forward position.
Lovaas in U.S. Pat. No. 5,067,766, Nov. 26, 1991 suggests a Telescoping Cover for A Pickup Truck Bed which has longitudinally telescoping cover members each having low side walls which are only as high as the cargo box walls, and a fully enclosed top. The telescoping cover members allow the operator to move a rear portion of the cover forward thereby leaving a rear portion of the cargo box open to hold large items. This cover has the same problems as Baranski in that it does not allow for the storage of items which are higher than the cargo box side walls when the cover is closed, and does not have an aesthetically pleasing side profile when in the forward position.
Miller in U.S. Pat. No. 5,127,701, Jul. 7, 1992 suggests a Shell For Bed Of Pick-Up Truck which shows a cap for a light truck which has a first portion fixed at the top of the cargo box of the truck which is a top extending rearwards from the cab of the truck and then slopes down towards the back of the truck and the second portion which extends rearwards from the first portion and is positioned above the sloping part of the first portion. The second portion is hinged at the start of the slope of the first portion and extends rearwards to the back of the truck box. The second portion can be flipped upwards allowing an object larger than the cap to be placed in the truck box beneath the second portion. This arrangement has the difficulty in that the second portion would be difficult to lift into the upright position, projects upward causing drag when the vehicle is in motion, and would tend to bounce up and down in response to bumps in the road possibly colliding with something placed beneath it.
R. J. Murphy in U.S. Pat. No. 2,602,693, Jul. 8, 1952 suggests a sliding closure. This sliding closure provides a plurality of telescoping cover members arranged and closed the open top of the box of a transport truck or van. The telescopic members extend rearwards from a container mounted on top of the cab of the truck or van and extend outwards along the length of the cargo box thereby enclosing the top. This enclosure requires that the sides of the cargo box be at the same height as the cab of the truck and therefore is not practical for use of most light duty and pick-up trucks.
A truck box cap for use with the open cargo box of a light duty truck is needed which is simple, provides an aesthetically pleasing side profile, protects the cargo box and its contents from snow, rain, or dirt that can cause damage to items being carried or stored in the cargo box, secures the items being carried or stored from theft, and permits the cargo box to be used to transport large items without having to remove the box cap.